Sounds like he's trying to make a stretchable 9-patch image, for making pretty boxes.

I was thinking about this just the other day - the four corners would be regular sprites (aligned TL, TR, BL, BR corners), the top and bottom would be a tiled background running left-right, the sides would be tiled backgrounds top-bottom, and the middle would be a regular tiled bg in all directions.

Then you could resize it at run-time and have all the parts snap to where they should be and have nice looking boxes for buttons, UI, etc. And I think he wants a way to automate this process.